Balers, specifically two ram balers, are commonly used to compress recyclable or waste material such as aluminum cans and the like into bales and then to strap the bales in order to facilitate transportation of the materials. Examples of such two ram balers are described in U.S. Pat. No. 5,007,337, entitled "Oversize Bale Release Mechanism For Waste Material Baler" and U.S. Pat. No. 5,081,922, entitled "Device for Controlling the Discharge of a Bale from a Solid Waste Baling Machine." These balers generally comprise a hopper for storing and feeding the material to be baled and a baling chamber in which the bale is formed. A main compression ram comprising a hydraulic plunger and platen is operated within the chamber to compress the material into the shape of the bale, and a smaller ram ejects the bale into the strapping device. Two knives or cutting edges are often used in order to separate the material in the hopper from the material in the baling chamber. One such cutting edge, the top cutting edge, is fixed to the top edge of the baling chamber where the material enters from the hopper. The other cutting edge, the bottom cutting edge, is attached to the top edge of the platen. As the hydraulic plunger extends, the top edge of the platen moves underneath the top of the baling chamber. Consequently, the two cutting edges meet in a scissor-type action to cut and separate material in the hopper from material in the baling chamber.
A problem arises as the bottom surface of the platen, which rides on the baling chamber floor, wears out, and the distance between the two cutting edges increases. As the distance increases, the cutting efficiency is reduced, much like the cutting efficiency of scissors is reduced if the connecting rivet loosens. As the cutting efficiency is reduced, total separation of the material is not accomplished. Damage to the baler may also occur.
This problem has been previously solved in one of two ways. The first technique is an adjustable top for the ceiling of the baling chamber. The top of the baling chamber is placed on shims and secured with bolts. As the bottom surface of the platen wears out, thus increasing the distance between the two cutting edges, the top of the baling chamber is removed. A number of shims are removed and the top of the chamber is reinstalled. The second method is to install shims underneath the floor of the baling chamber. As the bottom of the platen wears out, the number of shims is increased, thereby raising the platen and the lower cutting edge to the optimal level.
A problem with both of the above methods is that it takes substantial time and effort to remove the proper part at the proper time, change the number of shims, and then reinstall the removed part of the baler.
Another problem with the prior methods is that the baler operator is often not qualified to perform the adjustment. Professional service help must then be called in, resulting in more down time for the baler. Even where the operators are qualified to perform the adjustment, the time and effort required often results in the operator neglecting to correct the cutting edge distance when necessary. This neglect may result in inefficient baling or damage to the baler.